Continued advances in the speed and acuity of computers, particularly as related to graphics hardware and software, have recently made practical decades-old aspirations regarding immersive computer-generated environments. Virtual reality devices, with limb-tracking, haptic feedback, and head-mounted sensory equipment, are now being developed for consumer use. As cutting-edge systems attempt to provide more impressive and realistic artificial environments, the demands on the graphical systems remain intensive. In addition, efficient rendering and display, both in hardware and software, remain of paramount importance.
Advances in computer graphics and image technology have resulted in a new generation of head-mounted display devices with the intent to provide as realistic of a visual experience as possible for the user. The typical approach for these devices is to use conventional LCD display panels backed by frame-buffers that represent each pixel in the output frame.
This approach is wasteful in terms of power and area as it doesn't take account of the human visual system. The human retina has a high resolution at the center or fovea, a small region which is packed densely with photoreceptors and responsible for half the nerve fibers in the optic nerve. The rest of the retina provides lower resolution with a reduced density of photoreceptors. The human visual system gives the illusion of uniform high resolution by scanning the fovea around the scene and maintaining an internal mental model of the scene in the visual cortex.